The Skynet 2 satellite were assembled and tested at the Marconi Space and Defence Systems establishment in Portsmouth, England. The Skynet 2 system was very successful fot its time, and remained in service for several years beyond the originally planned timeframe.

Skynet 4 satellites have few similarities to the earlier generations. The cylindrical body of Skynet 1 and 2 was replaced by a large square body housing antennas with deployable solar-cell arrays. This marks the technological improvement from spin-stabilisation, used in earlier cylindrical satellites, to three-axis stabilisation using momentum wheels & reaction wheels controlling the satellite gyroscopically.

Skynet 4 were the first purely British built satellites, manufacture of 4A, 4B and 4C being carried out by British Aerospace Dynamics (BAe Dynamics). NATO adapted the design for the NATO IVA and IVB communication satellites, also manufactured by BAe Dynamics.

The improved Stage 2 satellites (4D, 4E and 4F) were built by Matra Marconi Space and Astrium to replace the earlier versions. Improvements included increased power and resistance to electronic jamming.

天網 5 係下一代嘅衞星，用來取代現有嘅天網 4 階段 2 系統。 It has been contracted via PFI to a partnership between Paradigm Secure Communications and EADS Astrium, a European spacecraft manufacturer. EADS Astrium will be responsible for the build and delivery of Skynet 5 satellites in orbit, whilst Paradigm will be responsible for provision of service to the MoD. Paradigm have also been contracted to provide communications services to NATO. The first of a constellation of three Skynet 5 vehicles was launched by a Ariane 5 rocket at 22:03 GMT on 11 March2007, aboard an Ariane 5expendable launch vehicle and will become operational following in-orbit testing. The launch was delayed from 10 March due to malfunction of a launch pad deluge system.

The programme marks a change of approach in the UK from traditional defence procurement methods to a services-based contract which also includes provision of leased ground terminals, Reacher vehicles and Satellite Communications Onboard Terminal SCOT ship fits and the associated baseband equipment.